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第41届中国控制会议

作者： Yuan Zhang Wanwei Huang Kunfeng Lu Honghao Zhong Beijing Aerospace Automatic Control Institute National Key Laboratory of Science and Technology on Aerospace Intelligent Control

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

A method for designing the finite-time prescribed performance controller with RBFNN(Radial Basis Function Networks) is proposed for the HFV(Hypersonic Flight Vehicle) longitudinal attitude systems with parameters uncertainties and time-varying ***,the appointed-time prescribed performance functions for outer-loop and inner-loop are designed respectively,which aims to restrain the transient and steady-state performance of command tracking *** with the traditional prescribed performance function,the proposed method can guarantee that the errors convergence to the set stability precision at the appointed ***,the error-transform function is applied to transform the guidance command errors into un-limited boundary,which can ensure the error satisfy the constraint condition by means of controlling the transformed ***,the virtual control law of outer-loop subsystem and the actual control law of inner-loop subsystem are designed independently,and the lumped disturbances are estimated by the RBFNN,a novel finite-time tracking differentiator is applied to avoid the 'explosion of terms' problem in the control law design ***,comparative simulations with parametric uncertainties and time-varying disturbance are performed to demonstrate that the proposed method in this paper can effectively satisfy the prescribed performance constraints.

关键词： Hypersonic flight vehicle Lumped Disturbance Finite-time control Radial Basis Function Networks Finite-time Tracking Differentiator

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Laser powder bed fusion of WE43 magnesium alloy with superior balance of strength and ductility

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Journal of Magnesium and Alloys 2025年第3期13卷 1275-1293页

作者： Wenhe Xu Jikang Li Zhenwu Zhang Hongwei Yuan Guojin An Hai Shi Chao Cai Wenming Jiang Wei Li Qingsong Wei State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Guizhou Aerospace Nanhai Science&Technology Co. Ltd.Zunyi 563000China Guizhou Aerospace Fenghua precision equipment Co. LtdGuiyang 550009China Key Laboratory of Metallurgical Equipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081China

WE43 is a high-strength magnesium alloy containing rare-earth elements such as Y,Gd and ***,how to further obtain the balance of strength and ductility,as well as the manufacture of complex structures is still a dilemma for its engineering *** this study,WE43 alloy samples withﬁne microstructures,high densiﬁcation and excellent mechanical properties were successfully prepared by laser powder bed fusion(LPBF)additive *** optimal process window was established,and the formation mechanisms of three types of porosity defects were revealed,namely lack-of-fusion pores,meltﬂuctuation-induced pores,and keyhole-induced *** the combined process of laser power of 200 W and scanning speed of 600 mm/s,samples with a high density of 99.89%were ***,periodic heterogeneous microstructure was prepared along the build direction,i.e.,ﬁne grains(∼4.1μm)at melt pool boundaries and coarse grain(∼23.6μm)inside melt *** was mainly due to the preferential precipitation of Zr and Mg_(3)(Gd,Nd)nano-precipitates at the melt pool boundaries providing nucleation sites for the *** special feature could provide an extra hetero-deformation induced(HDI)strengthening and retard *** optimal tensile yield strength,ultimate tensile strength and elongation at break were 276±1 MPa,292±1 MPa and 6.1±0.2%,*** obtained tensile properties were superior to those of other magnesium alloys and those fabricated by other *** solid solution strengthening(∼24.5%),grain boundary strengthening(∼14.4%)and HDI strengthening(∼32.2%)were the main sources of high yield *** work provides a guidance on studying the pore defect suppression and strengthening mechanisms of WE43 alloy and other magnesium alloys produced by LPBF.

关键词： Laser powder bed fusion(LPBF) WE43 alloy Pore defect Microstructure Strengthening mechanisms

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Application of Grey Wolf Optimization Algorithm in Tuning controller Parameters of Hypersonic Vehicle 41

Application of Grey Wolf Optimization Algorithm in Tuning Co...

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第41届中国控制会议

作者： Can Tian Shaobo Ni Zhaolei Wang Yuan Zhang National Key Laboratory of Science and Technology on Aerospace Intelligent Control Beijing Aerospace Automatic Control Institute

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

There are many adjustable parameters in the control method of predictive sliding mode control(PSMC) law and linear extended state observer(LESO) for hypersonic vehicle speed and altitude,and the adjustable parameters influence each other on the control effect,and the speed and altitude channels of the aircraft are coupled with each other,so the controller parameters cannot be independently tuned.A method of automatically tuning controller parameters by using grey wolf optimization(GWO) algorithm is ***,the fitness function containing the desired control effect is designed,and then the appropriate number of search agent and iteration times are *** simulation results show that the control effect of the controller with GWO tuning parameters is obviously better than that of the controller with experience tuning parameters,and the expected control effect can be achieved under the condition of adding parameter deviation and actuator limitation.

关键词： predictive sliding mode control linear extended state observer Grey Wolf optimization algorithm Auto-tuning controller parameters

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Predicting circRNA-Disease Associations by Using Multi-Biomolecular Networks Based on Variational Graph Auto-Encoder with Attention Mechanism

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Chinese Journal of Electronics 2024年第6期33卷 1526-1537页

作者： Jing YANG Xiujuan LEI Yi PAN School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Shenzhen Key Laboratory of Intelligent Bioinformatics Shenzhen Institute of Advanced Technology

CircRNA-disease association(CDA) can provide a new direction for the treatment of diseases. However,traditional biological experiment is time-consuming and expensive, this urges us to propose the reliable computational model to predict the associations between circRNAs and diseases. And there is existing more and more evidence indicates that the combination of multi-biomolecular information can improve the prediction accuracy. We propose a novel computational model for CDA prediction named MBCDA, we collect the multi-biomolecular information including circRNA, disease, miRNA and lncRNA based on 6 databases, and construct three heterogeneous network among them, then the multi-heads graph attention networks are applied to these three networks to extract the features of circRNAs and diseases from different views, the obtained features are put into variational graph auto-encoder(VGAE) network to learn the latent distributions of the nodes, a fully connected neural network is adopted to further process the output of VGAE and uses sigmoid function to obtain the predicted probabilities of circRNA-disease *** a result, MBCDA achieved the values of AUC and AUPR under 5-fold cross-validation of 0.893 and 0.887. MBCDA was applied to the analysis of the top-25 predicted associations between circRNAs and diseases, these experimental results show that our proposed MBCDA is a powerful computational model for CDA prediction.

关键词： Knowledge engineering Attention mechanisms Computational modeling Biological system modeling Predictive models Feature extraction Heterogeneous networks Topology Data mining Diseases

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Brockett's Second Example:A FAS Approach Treatment

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Journal of Systems science & Complexity 2023年第5期36卷 1789-1808页

作者： DUAN Guang-Ren Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China

In this paper,several equivalent forms of the well-known Brockett's second example system are firstly *** stabilization of the system is then treated in the fully actuated system approach.A simple continuous time-invariant sub-stabilizing controller is designed,and the corresponding region of attraction is *** a result,all trajectories of the system starting from the characterized region of attraction are driven exponentially to the *** the region of attraction is very large,the designed sub-stabilizing controller can be directly useful in many practical *** cases where the initial values are indeed needed to be chosen out of the region of attraction,extremely simple pre-controllers can be designed,which drive the system trajectories into the designed region of attraction.A simulation of the designed control system is carried out to show the effect of the proposed approach.

关键词： Brockett integrator continuous time-invariant controllers fully actuated system approach region of attraction sub-stabilization

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Event-triggered predefined-time control for full-state constrained nonlinear systems: A novel command filtering error compensation method

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science China(Technological sciences) 2024年第9期67卷 2867-2880页

作者： PAN YingNan CHEN YiLin LIANG HongJing College of Control Science and Engineering Bohai UniversityJinzhou 121013China School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing 100089China

In this paper, a command filter-based adaptive fuzzy predefined-time event-triggered tracking control problem is investigated for uncertain nonlinear systems with time-varying full-state constraints. By designing a sliding mode differentiator, the inherent computational complexity problem within the predefined-time backstepping framework is solved. Different from the existing command filter-based finite-time and fixed-time control strategies that the convergence time of the filtering error is adjusted through the system initial value or numerous parameters, a novel command filtering error compensation method is presented,which tunes one control parameter to make the filtering error converge in the predefined time, thereby reducing the complexity of design and analysis of processing the filtering error. Then, an improved event-triggered mechanism(ETM) that builds upon the switching threshold strategy, in which an inverse cotangent function is designed to replace the residual term of the ETM,is proposed to gradually release the controller's dependence on the residual term with increasing time. Furthermore, a tan-type nonlinear mapping technique is applied to tackle the time-varying full-state constraints problem. By the predefined-time stability theory, all signals in the uncertain nonlinear systems exhibit predefined-time stability. Finally, the feasibility of the proposed algorithm is substantiated through two simulation results.

关键词： predefined-time control command filtering error compensation method event-triggered mechanism time-varying full-state constraints uncertain nonlinear systems

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Chip Architecture Design Management Based on Low-Power Multitasking Simulation 9

Chip Architecture Design Management Based on Low-Power Multi...

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9th International Conference on Advances in Machinery, Materials science and Engineering Applications, MMSE 2023

作者： Zhang, Ying Sun, Kai National Key Laboratory of Science and Technology on Aerospace Intelligent Beijing Aerospace Automatic Control Institute Beijing100854 China

ISBN: (纸本)9781643684383

From the aspects of low-power DSP design, low-power SOC design, and low-power power switch design, this paper proposes a chip architecture 'high-low matching' scheme for low-power multitasking requirements. The low-power DSP design starts with operating voltage and operating frequency control, and uses three low-power modes, PD1, PD2, and PD3;the low-power SOC design carries out low-power mode management from the clock control of APB and AHB bus;In terms of low-power power switch design, no-load low-power control, and input under-voltage protection, output over-voltage protection, over-temperature protection, and output over-current protection are implemented. The paper proposes different low-power control modes. After the evaluation of the built test platform, it is proved that the design of the scheme is reasonable, and it can realize the engineering application of low-power multi-task management. © 2023 The Authors.

关键词： Electric power utilization

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Collision Avoidance Trajectory Planning of Cluster Spacecraft Considering Energy Optimization 7th

Collision Avoidance Trajectory Planning of Cluster Spacecraf...

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7th Chinese Conference on Swarm Intelligence and Cooperative control, CCSICC 2023

作者： Zhao, Teng Yin, Junxiong Tan, Xiaoyu Huang, Jingmei Zhou, Wei Shanghai Aerospace Control Technology Insititute Shanghai China Shanghai Key Laboratory of Space Intelligent Control Technology Shanghai China

ISBN: (纸本)9789819733354

Aimed at the matters of that it is a large fuel consumption, imbalance consumption and long time-consuming in the application of conventional cluster aggregation algorithm in cluster spacecraft trajectory planning, an energy optimal clustered collision avoidance algorithm based on centripetal aggregation was proposed. Firstly, based on the equation of Clohessy-Wiltshire of the cluster spacecraft and the model of the finite-time energy optimization, the algorithm established an adaptive centripetal aggregation energy optimization model. On this basis, for the matters of long time-consumed and collision, a clustering collision avoidance algorithm was proposed with optimal energy. The safe distance vector between modular spacecraft was used as the collision avoidance constraint, and the energy consumption was used as the clustering algorithm index. The simulation results show that the clustering algorithm can adaptively select the center of cluster spacecraft and collision-free effectively, reduce the total energy consumption of cluster spacecraft aggregation and the imbalance of energy consumption between modular spacecraft. So that the fluid consumption is globally optimal, and the time consumption is only in ten thousand of the conventional genetic algorithm. This algorithm provides an idea for r spacecraft rapid and safe clustering of cluster. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Collision avoidance

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Theoretical study on magnetocaloric effect and its electric-field regulation in CrI_(3)/metal heterostructure

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science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 134-141页

作者： Weiwei He Ziming Tang Qihua Gong Min Yi Wanlin Guo State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China

The extraordinary properties of a heterostructure by stacking atom-thick van der Waals(vdW)magnets have been extensively ***,the magnetocaloric effect(MCE)of heterostructures that are based on monolayer magnets remains to be ***,we deliberate MCE of vd W heterostructure composed of a monolayer CrI_(3)and metal atomic layers(Ag,Hf,Au,and Pb).It is revealed that heterostructure engineering by introducing metal substrate can improve MCE of CrI_(3),particularly boosting relative cooling power to 471.72μJ m^(-2)and adiabatic temperature change to 2.1 K at 5 T for CrI_(3)/*** improved MCE is ascribed to the enhancement of magnetic moment and intralayer exchange coupling in CrI_(3)due to the CrI_(3)/metal heterointerface induced charge *** field is further found to tune MCE of CrI_(3)in heterostructures and could shift the peak temperature by around 10 K in CrI_(3)/Hf,thus manipulating the working temperature window of *** theoretical results could enrich the research on low-dimensional magnetocaloric materials.

关键词： magnetocaloric effect heterostructure metal substrate

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A fully mesh-independent non-linear topology optimization framework based on neural representations:Quasi-static problem

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science China(Physics,Mechanics & Astronomy) 2025年第4期68卷 119-143页

作者： Zeyu Zhang Yu Li Weien Zhou Wen Yao College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China Defense Innovation Institute Chinese Academy of Military ScienceBeijing 100071China Intelligent Game and Decision Laboratory Beijing 100071China

In artificial intelligence(AI)for science,the AI-empowered topology optimization methods have garnered sustained attention from researchers and achieved significant *** this paper,we introduce the implicit neural representation(INR)from AI and the material point method(MPM)from the field of computational mechanics into topology optimization,resulting in a novel differentiable and fully mesh-independent topology optimization framework named MI-TONR,and it is then applied to nonlinear topology optimization(NTO)*** MI-TONR,the INR is combined with the topology description function to construct the design model,while implicit MPM is employed for physical response analysis.A skillful integration is achieved between the design model based on the continuous implicit representation field and the analysis model based on the Lagrangian *** with updating parameters of the neural network(i.e.,design variables),the structural topologies iteratively evolve according to the responses analysis results and optimization *** computational differentiability is ensured at every step of MI-TONR,enabling sensitivity analysis using automatic *** addition,we introduce the augmented Lagrangian Method to handle multiple constraints in topology optimization and adopt a learning rate adaptive adjustment scheme to enhance the robustness of the optimization *** examples demonstrate that MI-TONR can effectively conduct NTO design under large loads without any numerical techniques to mitigate numerical ***,its natural satisfaction with the no-penetration condition facilitates the NTO design of considering *** infinite spatial resolution characteristic facilitates the generation of structural topology at multiple resolutions with clear and continuous boundaries.

关键词： topology optimization implicit neural representation material point method automatic differentiation nonlinearity

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